Casp11 Deficiency Alters Subgingival Microbiota and Attenuates Periodontitis

Periodontitis (PD) is the primary cause of tooth loss in adults. Porphyromonas gingivalis (P.g), a keystone pathogen, has been identified as a crucial contributor to this process. Pyroptosis activation in PD is acknowledged, with accumulating evidence underscoring the crucial role of Caspase-11 (described as Caspase-4/5 in humans)-mediated noncanonical pyroptosis. However, the mechanism behind its impact on PD remains unclear. In this study, we delved into the interplay between the Caspase-11-mediated noncanonical pyroptosis, subgingival microbiota alteration, and macrophage polarization. Clinical samples from PD patients revealed heightened expression of Caspase-4, gasdermin-D, and their active fragments, pointing to the activation of the noncanonical pyroptosis. Single-cell sequencing analysis linked Caspase-4 with gingival macrophages, emphasizing their involvement in PD. In vitro cell experiments confirmed that P.g-induced pyroptosis was activated in macrophages, with Casp11 deficiency attenuating these effects. In an experimental PD mouse model, Casp11 deficiency led to an alteration in subgingival microbiota composition and reduced alveolar bone resorption. Casp11-/- mice cohousing with wild-type mice confirmed the alteration of the subgingival microbiota and aggravated the alveolar bone resorption. Notably, Casp11 deficiency led to decreased M1-polarized macrophages, corresponding with reduced alveolar bone resorption, uncovering a connection between subgingival microbiota alteration, macrophage M1 polarization, and alveolar bone resorption. Taken together, we showed that Caspase-11 fulfilled a crucial role in the noncanonical pyroptosis in PD, potentially influencing the subgingival microbiota and linking to M1 polarization, which was associated with alveolar bone resorption. These findings underscored the pivotal role of the Caspase-11-mediated noncanonical pyroptosis in PD pathogenesis and may provide critical insights into potential therapeutic avenues for mitigating PD.

Detection of novel drug-adverse drug reaction signals in rheumatoid arthritis and ankylosing spondylitis: analysis of Korean real-world biologics registry data

This study aimed to detect signals of adverse drug reactions (ADRs) associated with biological disease-modifying antirheumatic drugs (DMARDs) and targeted therapies in rheumatoid arthritis (RA) and ankylosing spondylitis (AS) patients. Utilizing the KOrean College of Rheumatology BIOlogics & Targeted Therapy Registry (KOBIO) data, we calculated relative risks, excluded previously reported drug-ADR pairs, and externally validated remaining pairs using US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and single centre's electronic health records (EHR) data. Analyzing data from 2279 RA and 1940 AS patients, we identified 35 significant drug-ADR pairs in RA and 26 in AS, previously unreported in drug labels. Among the novel drug-ADR pairs from KOBIO, 15 were also significant in the FAERS data. Additionally, 2 significant drug-laboratory abnormality pairs were found in RA using CDM MetaLAB analysis. Our findings contribute to the identification of 14 novel drug-ADR signals, expanding our understanding of potential adverse effects related to biological DMARDs and targeted therapies in RA and AS. These results emphasize the importance of ongoing pharmacovigilance for patient safety and optimal therapeutic interventions.

Effectiveness of next-generation sequencing for patients with advanced non-small-cell lung cancer: a population-based registry study

BACKGROUND

Despite the growing use of next-generation sequencing (NGS) in the management of advanced non-small-cell lung cancer (NSCLC), there is little evidence that its use leads to improved clinical outcomes. This study aimed to compare the effectiveness of NGS with that of single-gene testing (SGT) alone in patients with advanced NSCLC.

MATERIALS AND METHODS

This was a retrospective cohort study conducted on patients diagnosed with advanced lung adenocarcinoma between 2017 and 2018 from a nationwide, population-based database. We identified patients who had SGT exclusively (SGT group) or underwent upfront NGS or NGS following SGT as an initial evaluation (NGS group). Patients were followed up until death or the end of the study (31 December 2019). The adjusted hazard ratio (aHR) for death was estimated using the Cox proportional hazards model. The factors affecting the adoption of NGS were identified.

RESULTS

Of 8566 patients diagnosed with advanced lung adenocarcinoma, 402 and 6932 patients were assigned to the NGS and SGT groups, respectively. More NGS was carried out in younger patients, those with higher incomes, and those living in urban areas. After balancing these confounders through matching, no difference was observed in the median overall survival and risk of death between the NGS and SGT groups [18.5 versus 19.7 months, log-rank P = 0.783; aHR 0.98, 95% confidence interval (CI) 0.84-1.14, respectively]. Only in a subgroup for whom epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitors were not indicated, NGS was associated with better survival outcomes (14.1 versus 9.0 months, log-rank P = 0.006; aHR 0.82, 95% CI 0.69-0.97).

CONCLUSIONS

In the real world, NGS for all-comers in patients with advanced NSCLC did not increase survival outcomes. When health care resources to support equal access to NGS are limited, upfront SGT followed by NGS may be a more efficient strategy.

Surface-Modified Carbon Nanotubes with Ultrathin Co3O4 Layer for Enhanced Oxygen Evolution Reaction

Alkaline water electrolysis is a vital technology for sustainable and efficient hydrogen production. However, the oxygen evolution reaction (OER) at the anode suffers from sluggish kinetics, requiring overpotential. Precious metal-based electrocatalysts are commonly used but face limitations in cost and availability. Carbon nanostructures, such as carbon nanotubes (CNTs), offer promising alternatives due to their abundant active sites and efficient charge-transfer properties. Surface modification of CNTs through techniques such as pulsed laser ablation in liquid media (PLAL) can enhance their catalytic performance. In this study, we investigate the role of surface-modified carbon (SMC) as a support to increase the active sites of transition metal-based electrocatalysts and its impact on electrocatalytic performance for the OER. We focus on Co3O4@SMC heterostructures, where an ultrathin layer of Co3O4 is deposited onto SMCs using a combination of PLAL and atomic layer deposition. A comparative analysis with aggregated Co3O4 and Co3O4@pristine CNTs reveals the superior OER performance of Co3O4@SMC. The optimized Co3O4@SMC exhibits a 25.6% reduction in overpotential, a lower Tafel slope, and a significantly higher turnover frequency (TOF) in alkaline water splitting. The experimental results, combined with density functional theory (DFT) calculations, indicate that these improvements can be attributed to the high electrocatalytic activity of Co3O4 as active sites achieved through the homogeneous distribution on SMCs. The experimental methodology, morphology, composition, and their correlation with activity and stability of Co3O4@SMC for the OER in alkaline media are discussed in detail. This study contributes to the understanding of SMC-based heterostructures and their potential for enhancing electrocatalytic performance in alkaline water electrolysis.

Short-range end resection requires ATAD5-mediated PCNA unloading for faithful homologous recombination

Homologous recombination (HR) requires bidirectional end resection initiated by a nick formed close to a DNA double-strand break (DSB), dysregulation favoring error-prone DNA end-joining pathways. Here we investigate the role of the ATAD5, a PCNA unloading protein, in short-range end resection, long-range resection not being affected by ATAD5 deficiency. Rapid PCNA loading onto DNA at DSB sites depends on the RFC PCNA loader complex and MRE11-RAD50-NBS1 nuclease complexes bound to CtIP. Based on our cytological analyses and on an in vitro system for short-range end resection, we propose that PCNA unloading by ATAD5 is required for the completion of short-range resection. Hampering PCNA unloading also leads to failure to remove the KU70/80 complex from the termini of DSBs hindering DNA repair synthesis and the completion of HR. In line with this model, ATAD5-depleted cells are defective for HR, show increased sensitivity to camptothecin, a drug forming protein-DNA adducts, and an augmented dependency on end-joining pathways. Our study highlights the importance of PCNA regulation at DSB for proper end resection and HR.

Influence of Contrast Materials on Dose Accuracy of MR-Linac in Patients with SBRT Liver Cancer

PURPOSE/OBJECTIVE(S)

Objective: Intravenous injection of contrast agent during CT scanning can improve the accuracy of target area contouring, however the contrast agent will cause dose bias due to the high relative electron density. This study aims to explore the influence of contrast agent on the accuracy of dose calculation of the planning system during SBRT based on MRI-Linac for liver cancer treatment.

MATERIALS/METHODS

Methods: In this study, 20 patients undergoing stereotactic body radiation therapy (SBRT) for liver cancer were selected, and their complete unenhanced CT, contrast-enhanced CT, and corresponding structures were imported into Monaco V.5.4. The target and organs at risk (OARs) in the unenhanced CT and contrast-enhanced CT were additionally contoured according to the target contouring guidelines and OARs were ranked. The average relative electron densities of OARs (lung, spinal cord, heart, rib, etc.) were calculated with Monaco TPS. The reference plan is based on unenhanced CT for plan calculation (plan1). To compare the dosimetry errors caused by the synthetic CT, the average relative electron density of all structures in unenhanced CT was forced and the plans were recalculated (plan2). To investigate dosimetric differences caused by the changes of relative electron density due to the contrast agent, the average relative electron density of all structures in contrast-enhanced CT was forced and the plans were recalculated(plan3). The dosimetric differences in groups A (plan 1 and plan2), B (plan 1 and plan3), and C (plan2 and plan3) were compared, respectively.

RESULTS

There were not significant difference between three groups in the affected lung, heart, liver, blood, all within 3%. However, differences were significantly different in the group B. The maximum deviation of spinal cord Dmax reached 4.78%. In addition, the deviation of the dose parameters in the target area was small, except that the maximum deviation of the CI value in group B was 3.23%.

CONCLUSION

For SBRT planning of liver cancer based on magnetic resonance accelerator, synthetic CT has little influence on the calculation of planned dose. The dose difference caused by contrast materials is also relatively small, although the deviation of the CI value of the target area exceeds 3%, which is also within the clinical acceptance range. However, the deviation of the maximum value of the spinal cord is relatively large, exceeding the clinically acceptable range. Therefore, when optimizing the SBRT plan for liver cancer, attention should be paid to important organs such as the spinal cord, and should be avoided as far as possible when setting the fields.

Effectiveness of Bladder Filling Control during Online MR-Guided Adaptive Radiotherapy for Rectum Cancer

PURPOSE/OBJECTIVE(S)

MR-guided adaptive radiotherapy (MRgART) treatment sessions at MR-Linac are time-consuming and changes in bladder filling during the session can impact the treatment dosimetry. In this work, we present the procedure implemented in the clinical workflow to stabilize bladder filling during the MR based adaptive radiotherapy sessions and evaluate its effectiveness and the resulting dosimetric impact on the adaptive plan.

MATERIALS/METHODS

Twenty-five rectum cancer patients treated at 1.5T MR-Linac with a short course radiotherapy (25 Gy in 5 fractions of 5 Gy each) were included in this retrospective study. Patients were treated with the adapt-to-shape workflow consisting of a plan adaptation based on the MRI acquired in each session and optimized on the corresponding MR-based synthetic CT. Considering the significant interval time between the acquisition of the first daily MRI used for plan adaptation, and the beam delivery, a bladder catheter was used to stabilize the bladder filling; the procedure consists of emptying the bladder and refilling it with a well-known amount of physiological solution before each MRI acquisition. Two MRIs were acquired at each session: the first was used for plan adaptation and the second was acquired while approving the adapted plan, to be rigidly registered with the first to ensure the appropriateness of the isodoses on the ongoing delivery treatment. A total of 125 sessions and 250 MRI images and bladder contours were analyzed; for each fraction, the time interval between the first and second MRI and the corresponding bladder volumes were recorded; the consistency of bladder volumes and shapes along each online session was assessed with the dice similarity index (DSC) and Hausdorff distance (HD); the impact on plan dosimetry was evaluated by comparing target and bladder DVH cut off points of the plan on the two different MRI datasets.

RESULTS

The time interval between the first and second MRI, averaged over the 125 sessions is 39.0 min, range (18.6-75.8) min. The changes in bladder volumes, DSC index, HD, and the differences between the bladder and target DVH cut-off points are shown in the table below. The DSC and HD are comparable to inter-observer variability in manual contour segmentation, with an average DSC of 0.91 and average HD of 2.13 mm; the average differences in bladder and target dosimetry remain under 0.63% and 0.10%, respectively.

CONCLUSION

The use of a procedure in the clinical workflow of MRgART to stabilize the bladder filling throughout the online session may be helpful to guarantee the accuracy of the ongoing delivered treatment.

Search for a τ^{+}τ^{-} Resonance in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} Events with the Belle II Experiment

We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} events in the 3.6-10  GeV/c^{2} mass range. We use a 62.8  fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5  GeV/c^{2} and for the axionlike particle model over the entire mass range.

Measurement of CP Violation in B^{0}→K_{S}^{0}π^{0} Decays at Belle II

We report a measurement of the CP-violating parameters C and S in B^{0}→K_{S}^{0}π^{0} decays at Belle II using a sample of 387×10^{6}  BB[over ¯] events recorded in e^{+}e^{-} collisions at a center-of-mass energy corresponding to the ϒ(4S) resonance. These parameters are determined by fitting the proper decay-time distribution of a sample of 415 signal events. We obtain C=-0.04_{-0.15}^{+0.14}±0.05 and S=0.75_{-0.23}^{+0.20}±0.04, where the first uncertainties are statistical and the second are systematic.

First-principles evaluation of dopant impact on structural deformability and processability of Li7La3Zr2O12

Li7La3Zr2O12 (LLZO) and related ceramic solid electrolytes feature excellent stability and reasonable ionic conductivity, but processing remains challenging. High-temperature co-sintering is required for successful integration with the electrode, which is energetically costly and can lead to unacceptable cathode degradation. The introduction of dopants can promote lower-temperature processing by improving deformability and disrupting lattice integrity; however, an unbiased, systematic study correlating these properties to the dopant chemistry and composition is lacking. Here, we rely on a set of static and dynamic metrics derived from first-principles simulations to estimate the impact of doping on LLZO processability by quantifying LLZO structural deformability. We considered three distinct dopants (Al, Ba, and Ta) as representatives of substitutional incorporation on Li, La, and Zr sites. Our descriptors indicate that doping in general positively impacts lattice deformability, although significant sensitivities to dopant identity and concentration are observed. Amongst the tested dopants, Al doping (on the Li site) appears to have the greatest impact, as signaled across nearly the entire set of computed features. We suggest that these proxy descriptors, once properly calibrated against well-controlled experiments, could enable the use of first-principles simulations to computationally screen new ceramic electrolyte compositions with improved processability.

Delayed immune-mediated hepatitis after three cycles of pembrolizumab for the treatment of sinonasal melanoma

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that induce the anti-tumor effects of T cells by targeting co-inhibitory immune checkpoints. The development of ICIs has revolutionized the clinical practice of oncology, leading to significant improvements in outcomes; therefore, ICIs are now standard care for various types of solid cancers. Immune-related adverse events, the unique toxicity profiles of ICIs, usually develop 4-12 weeks after initiation of ICI treatment; however, some cases can occur >3 months after cessation of ICI treatment. To date, there have been limited reports about delayed immune-mediated hepatitis (IMH) and histopathologic findings. Herein, we present a case of delayed IMH that occurred 3 months after the last dose of pembrolizumab, including histopathologic findings of the liver. This case suggests that ongoing surveillance for immune-related adverse events is required, even after cessation of ICI treatment.

Search for an Invisible Z^{'} in a Final State with Two Muons and Missing Energy at Belle II

The L_{μ}-L_{τ} extension of the standard model predicts the existence of a lepton-flavor-universality-violating Z^{'} boson that couples only to the heavier lepton families. We search for such a Z^{'} through its invisible decay in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'}. We use a sample of electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019-2020, corresponding to an integrated luminosity of 79.7  fb^{-1}. We find no excess over the expected standard-model background. We set 90%-confidence-level upper limits on the cross section for this process as well as on the coupling of the model, which ranges from 3×10^{-3} at low Z^{'} masses to 1 at Z^{'} masses of 8  GeV/c^{2}.

Search for Lepton-Flavor-Violating τ Decays to a Lepton and an Invisible Boson at Belle II

We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→μ^{-}α decays, where α is an invisible spin-0 boson. The search uses electron-positron collisions at 10.58 GeV center-of-mass energy with an integrated luminosity of 62.8  fb^{-1}, produced by the SuperKEKB collider and collected with the Belle II detector. We search for an excess in the lepton-energy spectrum of the known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} and τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ} decays. We report 95% confidence-level upper limits on the branching-fraction ratio B(τ^{-}→e^{-}α)/B(τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ}) in the range (1.1-9.7)×10^{-3} and on B(τ^{-}→μ^{-}α)/B(τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}) in the range (0.7-12.2)×10^{-3} for α masses between 0 and 1.6  GeV/c^{2}. These results provide the most stringent bounds on invisible boson production from τ decays.

Effects of an Acidic Environment on the Strength and Chemical Changes of Resin-based Composites

The objective of this study was to evaluate the aging effects of long-term exposure to acidic beverages on the flexural strength (FS) and chemical reactions of two resin-based composites (RBCs) and one giomer. The FS of composite specimen bars (2 mm × 2 mm × 25 mm) was measured using a universal testing machine at various levels of thermocycling (TC; 0, 10,000, 50,000, and 100,000 cycles) in two beverages with different pH values (distilled water [DW], pH 7.0; Coca-Cola, pH 2.4-2.8). The FS data were analyzed using three-way analysis of variance with the post hoc Tukey test and t-test at a significance level of a=0.05. In DW, the FS of an RBC and a giomer did not decrease until 10,000 cycles. The other RBC, Z250, decreased rapidly until 50,000 cycles (p<0.05), followed by no additional decrease until 100,000 cycles. In Coca-Cola, the FS of two RBCs and a giomer decreased more rapidly than in DW from 10,000 cycles (t-test, p<0.05). In Coca-Cola, the increased porosity observed in scanning electron microscopy (SEM) images, the changes of the hydroxyl peak at 3340 cm-1 and ester peak at 1730-1700 cm-1 in Fourier-transform infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR) spectra, and the continuous increase of the Si-O/Si-C peak height ratio from 10,000 cycles to 100,000 cycles in X-ray photoelectron spectroscopy (XPS) suggested an increased loss of silane-carbon bond between the matrix and fillers of the Z250 RBC, compared to those in DW. In conclusion, when TC was performed in DW, unreacted monomers and a coupling agent were washed out, which caused porosity and reduced FS. In Coca-Cola, acidic conditions accelerated the removal of the matrix through the hydrolysis reaction at the ester groups, resulting in more porosity and a faster decrease in FS than in DW.

Effect of food additives on key bacterial taxa and the mucosa-associated microbiota in Crohn's disease. The ENIGMA study

Food additives have been linked to the pro-inflammatory microbial dysbiosis associated with Crohn's disease (CD) but the underlying ecological dynamics are unknown. Here, we examine how selection of food additives affects the growth of multiple strains of a key beneficial bacterium (Faecalibacterium prausnitzii), axenic clinical isolates of proinflammatory bacteria from CD patients (Proteus, Morganella, and Klebsiella spp.), and the consortia of mucosa-associated microbiota recovered from multiple Crohn's disease patients. Bacterial growth of the axenic isolates was evaluated using a habitat-simulating medium supplemented with either sodium sulfite, aluminum silicate, carrageenan, carboxymethylcellulose, polysorbate 80, saccharin, sucralose, or aspartame, intended to approximate concentrations found in food. The microbial consortia recovered from post-operative CD patient mucosal biopsy samples were challenged with either carboxymethylcellulose and/or polysorbate 80, and the bacterial communities compared to unchallenged consortia by 16S rRNA gene amplicon profiling. Growth of all F. prausnitzii strains was arrested when either sodium sulfite or polysorbate 80 was added to cultures at baseline or mid-exponential phase of growth, and the inhibitory effects on the Gram-negative bacteria by sodium sulfite were conditional on oxygen availability. The effects from polysorbate 80, saccharin, carrageenan, and/or carboxymethylcellulose on these bacteria were strain-specific. In addition to their direct effects on bacterial growth, polysorbate 80 and/or carboxymethylcellulose can drive profound changes in the CD mucosa-associated microbiota via niche expansion of Proteus and/or Veillonellaceae - both implicated in early Crohn's disease recurrence. These studies on the interaction of food additives with the enteric microbiota provide a basis for dietary management in Crohn's disease.

PCNA Ser46-Leu47 residues are crucial in preserving genomic integrity

Proliferating cell nuclear antigen (PCNA) is a maestro of DNA replication. PCNA forms a homotrimer and interacts with various proteins, such as DNA polymerases, DNA ligase I (LIG1), and flap endonuclease 1 (FEN1) for faithful DNA replication. Here, we identify the crucial role of Ser46-Leu47 residues of PCNA in maintaining genomic integrity using in vitro, and cell-based assays and structural prediction. The predicted PCNAΔSL47 structure shows the potential distortion of the central loop and reduced hydrophobicity. PCNAΔSL47 shows a defective interaction with PCNAWT leading to defects in homo-trimerization in vitro. PCNAΔSL47 is defective in the FEN1 and LIG1 interaction. PCNA ubiquitination and DNA-RNA hybrid processing are defective in PCNAΔSL47-expressing cells. Accordingly, PCNAΔSL47-expressing cells exhibit an increased number of single-stranded DNA gaps and higher levels of γH2AX, and sensitivity to DNA-damaging agents, highlighting the importance of PCNA Ser46-Leu47 residues in maintaining genomic integrity.

OS10.6.A What is the initial cell in the subventricular zone for human glioblastoma genesis?

Background

We all have a fundamental question about why glioblastoma (GBM) develops. In order to find the answer to this fundamental question, if you find out what the first cell is, you will get closer to the answer. GBM arises from the subventricular zone (SVZ). GBM is one of the most devastating tumour of human brain as the most optimal treatment barely prolongs the survival, and it does not cure the disease. As the majority of GBM tissues show copy number variations (CNV) of co-altered chromosomal 7 gain and 10 loss, we hypothesized the origin cell (Oc) of SVZ may be traced back with these markers. The cellular identity of the Oc is still unknown and it is different from the tumour-derived progenitor-like cells. We aimed to define these cells from the SVZ that have a potential to get activated into GBM.

Material and Methods

We compared bulk RNA sequencing (RNAseq) data of IDHwt GBM tumor tissue (n=122), tumor free SVZ from GBM patients (n=40), tumor-free control SVZ of non-glial tumor (n=9). Pared single nucleus RNAseq (snRNAseq) or single cell RNAseq (scRNAseq) samples of tumor free SVZ (n=11) and GBM tumor (n=8), were done to see cell specific CNVs. We developed genetically engineered mouse models for GBM genesis introducing three driver mutations (TP53, PTEN, and EGFRviii) into SVZ to isolate mouse Oc (mOc) and mouse cancer cells (mCc). The biological characteristics of separated mOc and mCc were compared. Bulk RNAseq and scRNAseq were performed on these cells (mOc, mCc), and their cellular state was compared with the human gene set.

Results

In this work, we found two types of the Oc in the RNA sequencing of 60 human tumour free-SVZ samples. Furthermore, single-cell level analysis revealed that two Oc types in SVZ harbor ongoing patterns of CNV co-alterations from Oc1 to Oc2, and finally to GBM. The Oc1 type cells contained the CNV signature of Oc2 ancestor with neural progenitor cell (NPC) signature. Oc2 type cells expressed a high level of EGFR than other cells with astrocyte-like cell signature. Both of these cells expressed oligodendrocyte progenitor cell (OPC)-like signatures in the SVZ. We validated the human-based findings by using the P53/PTEN/EGFR-mutant mouse model with EGFR/tdTomato overexpression and P53/PTEN knockout in the SVZ cells. As a result, non-tumourigenic and highly motile Oc-like cell-states are found in the mouse models, supporting the firework-like migration pattern from the SVZ.

Conclusion

Our results demonstrate how members of Oc preoccupy the SVZ, known as the stem cell niche and give rise to the tumour. We anticipate that a new therapy may emerge by targeting the Oc in the SVZ.

P12.04.A Exosomes from glioma associated sphere forming cells induce a transition of invasive phenotype via transfer of EMP2 and CA9

Background

Glioblastoma multiforme (GBM) mostly occurs local recurrence at normal parenchyme adjacent tumor despite of conventional treatment. Glioma stem like cells (GSC) forming intratumoral heterogeneity within the GBM acquired the microenvironmental adaptation by inter-exosomal contents exchange between heterogenic cells. In addition, GSC has an invasive potential as like human GBM. Therefore, we investigate whether exosomal proteins of GSC affect the normal tissue invasion in GBM.

Material and Methods

Exosomes were isolated by Size-Exclusion method from conditioned media and validated by Electron microscope and Immunoblot assay. Exosomal proteomics were examined with Liquid Chromatography-Mass Spectrometry (LC/MS). To produce the fluorescent exosome, bi-cistron vectors were cloned with shRNA and CD63-GFP. To identify the effect of tranfected exosome, the isolated exosomes were treated to recipient cells and examined the invasion by 3D invasion assay and mouse intracranial model.

Results

Firstly, we dichotomized two groups following tumor invasion at matrigel assay and GSC derived orthotopic mouse model. CSC2 and X01 GSCs revealed highly invasive phenotype whereas 83NS and 528NS GSCs did not. Exosome was isolated in each group and identified by CD63 expression or electron microscopy. In proteomics analysis, hypoxia, extracellular matrix organization, GTPase cycle related proteins were enriched in highly invasive cell’s exosome. Among them, we focused the carbonic anhydrase IX (CA9) and the epithelial membrane protein 2 (EMP2) on its permissive role to glioblastoma invasion respectively. CA9 and EMP2 mRNA and protein levels were verified in GSCs and their exosomes and the high expression levels were detected in CSC2 and X01 compared to the low one in 83NS and 528NS GSCs. To evaluate the effects of CA9 and EMP2 on exosome mediated invasion potential, viral bi-cistron vectors was composed with the target gene knockdown and the CD63 fluorescence was used to detect intracellular exosome transfer. Interestingly, the decreased expression of phosphorylated FAK, a key invasive marker, was observed after Lentiviral mediated CA9- and EMP2-knockdown in highly invasive CSC2. To identify whether CA9 and EMP2 proteins are the intracellular effector protein responsible for exosome mediated glioma invasion, the donor exosomes (Exo-CSC2-sh-CA9 and Exo-CSC2-EMP2, after Lentiviral transfection to CSC2s) were isolated and treated to the non invasive 528NS cells as recipient cells. In 3D invasion assay, Exo-CSC2-shCA9 or Exo-CSC2-shEMP2 mediated tumor invasion was significantly decreased at 528NS GSCs compared to Exo-CSC2-shEV. These features were found at mouse intracranial model as well.

Conclusion

Together with these, we conclude that exosome derived from GSCs induces a transition of invasive phenotype via transfer of EMP2 and CA9 proteins.

P10.07.B Differential YAP activity in human glioblastoma tumorspheres

Background

Although glioblastoma (GBM) is the most common primary brain tumor, the best available treatment options are still associated with poor prognosis. Recently, the Hippo/YAP signaling pathway has been emerged as an important driver of GBM. Nevertheless, extensive studies have not yet been focused on the importance of phosphorylation event in regulating endogenous YAP activity in GBM. Here, we sought to elucidate that the modulation and stabilization of YAP/TAZ in Hippo pathway promotes GBM progression.

Material and Methods

Expression patterns of YAP1, TAZ, CTGF, TEAD4 and LATS1 mRNA were confirmed in human normal and GBM tissue, and patient survival according to YAP1 expression was confirmed in TCGA and Severance cohort. The YAP1 expression patterns in several TSs were classified into SOH and AH according to transcriptome analysis and western blot. For each classified TSs, the characteristics of SOH and AH were comparatively analyzed through immunoprecipitation, nucleus fraction, TEAD4 luciferase assay, and confocal analysis. The effect of YAP1 knockdown/out and overexpression in SOH and AH TSs were measured by WST/ATP analysis, 3D invasion and neurosphere formation, and western blot. In addition, the drug reactivity of SOH and AH TSs was examined by treatment with the YAP1 inhibitors Peptide17 and verteporfin, and the effects of Peptide17, verteporfin and YAP1-shRNA were examined in in-vivo xenograft model.

Results

YAP1 mRNA levels including TAZ, CTGF, TEAD4 and LATS1 were higher in GBM than in normal tissues. Through transcriptome analysis and western blot, TS can be divided into SOH and AH groups according to the expression level of CTGF, but not YAP1 level. In the case of SOH TS, the binding of TEAD4 was strong in immunoprecipitation, the ratio of YAP1 was higher in the nucleus in the nucleus fractionation and confocal analysis, and the luciferase activity of TEAD4 was high in the TEAD4 luciferase assay. On the other hand, in the case of TS of AH, the opposite trend was observed. When YAP1 was knocked down or out, the proliferation, invasion, and stemness of TS tended to be decrease more in SOH TS than in AH TS, and SOH TS showed more sensitive drug response even in Peptide17 and Verteporfin treatment. In the case of YAP1 overexpression, the opposite trend was observed in SOH TS. In the in-vivo xenograft model, injection of Peptide17, verteporfin, and YAP1-shRNA showed a tendency to increase the survival rate of mice.

Conclusion

The association of YAP has been described in several cancers, but there has been no study comparing GBM TS by YAP expression and classifying it at the functional level. Now, for the first time, we show that the characteristics of GBM TS can be predicted according to the expression value of YAP, respectively, and YAP is expected to be applied as an important prognostic factor for GBM treatment in the future.

Antidepressant medication and risk of cardiovascular disease in posttraumatic stress disorder patients: application of marginal structural models in Korean National Health Insurance Database

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): - National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT

Introduction

Previous evidence on antidepressant medication and cardiovascular disease (CVD) in posttraumatic stress disorder (PTSD) patients is mixed. We evaluated associations between antidepressant medication and CVD by applying marginal structural model.

Methods

We gathered medical utilization records of 27,170 patients diagnosed with PTSD in years 2004 - 2018 without prior CVD diagnosis from Korean National Health Insurance Database (NHID). PTSD and CVD were characterized in correspondence of ICD-10 diagnostic codes. We acquired information on antidepressant use from medical utilization records and categorized by medication category: selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs) and tricyclic antidepressants (TCAs). Discrete-time survival analysis with marginal structural inverse probability weighting was used to test association between antidepressants and CVDs and were compared to results from traditional time-fixed model and simple time-varying model. We calculated cumulative daily defined doses (DDDs) of each antidepressant categories and conducted polynomial splining to test dose response.

Results

SSRI use was associated with acute coronary syndrome (hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.26 - 1.86) and ischemic stroke (HR 1.33, 95% CI 1.08 - 1.63). SNRI use was associated with acute coronary syndrome (HR 1.52, 95% CI 1.09 - 2.12). TCA use was associated with acute coronary syndrome (HR 1.54, 1.21 - 1.96) and ischemic stroke (HR 1.34, 1.06 - 1.70). Polynomial spline showed positive dose-response in association between antidepressant use and CVD.

Conclusion

Antidepressant use is causally associated with CVD in patients with PTSD. Higher cumulative DDD of antidepressant increases the risk of CVD.

Distinct Motifs in ATAD5 C-Terminal Domain Modulate PCNA Unloading Process

Proliferating cell nuclear antigen (PCNA) is a DNA clamp that functions in key roles for DNA replication and repair. After the completion of DNA synthesis, PCNA should be unloaded from DNA in a timely way. The ATAD5-RFC-Like Complex (ATAD5-RLC) unloads PCNA from DNA. However, the mechanism of the PCNA-unloading process remains unclear. In this study, we determined the minimal PCNA-unloading domain (ULD) of ATAD5. We identified several motifs in the ATAD5 ULD that are essential in the PCNA-unloading process. The C-terminus of ULD is required for the stable association of RFC2-5 for active RLC formation. The N-terminus of ULD participates in the opening of the PCNA ring. ATAD5-RLC was more robustly bound to open-liable PCNA compared to the wild type. These results suggest that distinct motifs of the ATAD5 ULD participate in each step of the PCNA-unloading process.

AB0838 The Impact of Comorbidities on Patients with Axial Spondyloarthritis: A Cluster Analysis

Background

Previous study using cluster analysis technique analyzed the association between comorbidities and various outcome measures in patients with axial spondyloarthritis (axSpA). Due to the cross-sectional nature of the study, however, prognostic information about each group were not provided.

Objectives

This study aims to perform cluster analysis to differentiate axSpA patients in terms of comorbidities and to examine the differential treatment outcomes of these groups using the data retrieved from Korean College of Rheumatology Biologics (KOBIO) registry which includes longitudinal data of axSpA patients using anti-TNF agents.

Methods

Clinical characteristics and demographic data of axSpA patients in KOBIO registry were analyzed using an agglomerative hierarchical cluster analysis. The optimum number of clusters was determined by the pseudo-F statistic. After clustering, baseline clinical characteristics and treatment outcomes were compared between isolated axSpA and classified comorbidity groups using multivariable linear models and mixed linear models, respectively.

Results

1,207 patients were included in the study. At least one comorbidity was seen in 464 (38%) axSpA patients. Compared with those with isolated axSpA, patients with comorbidity were older, longer disease duration, and reported higher PtGA (p = 0.019), and BASFI (p <0.001), but did not have significantly different BASDAI, ESR, and CRP levels. The most common comorbidities were hypertension (14.4%), hyperlipidemia (13.0%), and obesity (4.5%). The hierarchical cluster analysis classified patients in 21 groups. We combined clusters 17-21 for further evaluation due to the small size of clusters (<5 patients). In multivariable linear models for baseline clinical characteristics, we found that patients in the hypothyroidism, asthma, and headache clusters reported poorer PtGA, BASDAI, or BASFI, and the weight loss cluster had higher level of CRP, compared with patients with isolated axSpA even after adjustment of patient demographic data. After 1-year treatment of anti-TNF agents, the patients in the hypothyroidism and weight loss clusters decreased greater amounts of BASDAI and BASFI scores and ESR/CRP levels, respectively, compared with patients with isolated axSpA (Table 1). However, the degree of improvement in asthma and headache clusters, which had higher disease activities at baseline, was similar with isolated axSpA. Therefore, they still had higher disease activity scores at the 1-year follow-up.

Table 1.

Comparing each cluster to patients with isolated axSpA (i.e. no comorbidity) using multivariable linear mixed models for each treatment outcome measure at 1-year follow-up as the dependent variable.

Cluster/descriptionPtGABASDAIBASFIESRCRP2isolated axSpA-----3Obesity0.233 (-0.57 - 1.036)0.098 (-0.648 - 0.844)-0.078 (-0.811 - 0.656)9.005 (0.481 - 17.529)†0.358 (-0.553 - 1.269)10Hypothyroidism-1.243 (-3.139 - 0.653)-2.147 (-3.908 - -0.385)†-2.38 (-4.076 - -0.684)†2.234 (-18.11 - 22.578)-0.087 (-2.123 - 1.95)11Weight loss-0.618 (-2.804 - 1.568)-0.901 (-2.932 - 1.131)-1.93 (-3.886 - 0.026)-26.891 (-50.351 - -3.431)†-4.197 (-6.544 - -1.849)†15Asthma0.049 (-2.138 - 2.235)0.833 (-1.199 - 2.864)0.254 (-1.702 - 2.209)-1.058 (-24.517 - 22.402)2.018 (-0.552 - 4.589)16Headache-0.103 (-1.052 - 0.846)0.169 (-0.713 - 1.051)0.463 (-0.387 - 1.312)0.344 (-9.693 - 10.382)-0.046 (-1.132 - 1.04)

† p-value < 0.05

. Only clusters including significant results were shown due to the limitation oft he number of characters.

Conclusion

Comorbidity could affect the treatment outcomes in patients with axSpA in certain subgroups. Thus, we should also pay attention to the comorbidities when treating axSpA.

Disclosure of Interests

None declared

POS0211 ASSOCIATION BETWEEN CARDIOVASCULAR OUTCOME AND RHEUMATOID ARTHRITIS: NATIONWIDE POPULATION-BASED COHORT STUDY

Background

Many studies have shown increased risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA). Despite a growing burden posed by CVD in RA patients, large scale studies which examined the association between characteristic of RA patients and CVD risks, and studies which adjusted for various confounding factors are lacking.

Objectives

This study aimed to investigate the association between CVD risk and RA in large-scale, nationwide cohort of Korean population, and to examine which characteristics of RA patients are associated with increased CVD risk.

Methods

We enrolled 136,469 patients with RA who participated in national health examinations within 2 years of RA diagnosis between 2010 and 2017 and non-RA controls matched by age and sex (n= 682,345). The cohort was followed until the end of 2019. The outcome was occurrence of myocardial infarction (MI) or stroke. MI was defined as one hospitalization or two outpatient visit with ICD-10-CM codes I21 or I22. Stroke was defined as one hospitalization with ICD-10-CM codes I63 or I64 and a claim for brain imaging (CT or MRI). The Cox proportional hazard model and Kaplan Meier curve were used for the analysis.

Results

Mean follow up duration was 4.7 years. The incidence rate of CVD was higher in RA group than control (MI: 3.20 vs 2.08; stroke: 2.84 vs 2.33 per 1,000 person-years). The risk of CVD was higher in RA patients. (MI: adjusted HR 1.54, 95% CI 1.46-1.61; Stroke: adjusted HR 1.22, 95% CI 1.16-1.28). The association between RA and CVD was prominent in female (MI: adjusted HR 1.41 in male, 1.60 in female, p for interaction = 0.0293; Stroke: adjusted HR 1.13 in male, 1.27 in female, p for interaction = 0.03) and younger-age subgroups (MI: adjusted HR 2.9 in <40 years, 1.52 in 40-64 years, 1.51 in ≥65 years, p for interaction<0.0001; Stroke: adjusted HR 2.35 in <40 years, 1.21 in 40-64 years, 1.21 in ≥65 years, p for interaction = 0.0100) after adjusting for confounding variables. The association between RA and risk of MI was significant in those without DM. (adjusted HR 1.30 in DM, 1.61 in non-DM, p for interaction = 0.0005)

Conclusion

RA patients had increased risk of CVD events compared to age- and sex-matched control group, and this association was stronger in female and younger-age subgroups. Therefore appropriate screening for CVD would be important in all RA patients including female and younger patients.

Disclosure of Interests

None declared

POS0803 INCREASED RISK OF MALIGNANCY IN PATIENTS WITH TAKAYASU’S ARTERITIS: A POPULATION-BASED COHORT STUDY IN KOREA

Background

Recent studies have identified neoplasms as the second most common cause of death in patients with Takayasu’s arteritis (TAK) [1,2]. Various autoimmune diseases are related to the increased rates of malignancies. Despite conflicting data, most studies concluded that there is no increase in the risk of malignancies in giant cell arteritis [3]. In the case of TAK, there have been few reports of malignancies [4]. However, only one study compared the risk of malignancies in TAK to that of the general population [5]. Because the previous study only included 180 patients with TAK from single center, no definite conclusion could be drawn. Here, we evaluated the relative risk of malignancies in patients with TAK and compared them with the general population using the medical insurance data of South Korea.

Objectives

This study aimed to evaluate the relative risk of malignancy in patients with TAK compared to that in the general population.

Methods

This retrospective nationwide cohort study used data from the Korean Health Insurance Review and Assessment Service database. All newly diagnosed patients with Takayasu’s arteritis were identified between January 2009 and December 2019. They were observed until the diagnosis of malignancy, death, or end of the observational period, December 2020. The occurrence of malignancy was regarded as the first claim under ICD-10 codes, including C00–97, D46, and D47.1, according to the incidence of malignancy classification published by the National Cancer Registry (NCR). The incidence of malignancy in the general population was retrieved from the 2014 NCR, which collects the annual incidence of malignancies in the entire population of South Korea. The standardized incidence ratios (SIRs) of the overall and site-specific malignancies were estimated and compared with the incidence of cancer in the general population.

Results

We identified 1,449 newly diagnosed patients with Takayasu’s arteritis during the observational period (9,196 person-years). A total of 74, 66, and 8 patients had overall, solid, and hematologic malignancies, respectively. The risks of overall (SIR, 1.62; 95% confidence interval [CI], 1.27–2.03), solid (SIR, 2.04; 95% CI, 1.56–2.61), and hematologic (SIR, 4.05; 95% CI, 3.72–7.98) malignancies were increased compared to those in the general population. In solid malignancies, breast (SIR, 2.07; 95% CI, 1.16–3.42), ovarian (SIR, 4.45; 95% CI, 1.21–11.39), and major salivary gland (SIR, 19.04; 95% CI, 2.31–68.76) cancers had an increased risk. In hematologic malignancies, the risk of myelodysplasia increased (SIR, 18.02; 95% CI, 3.72–52.66). Immunosuppressive agent use was not associated with malignancy. There was no specific period when cancer more frequently occurred.

Conclusion

An increased risk of malignancy was observed in patients with Takayasu’s arteritis compared to that in the general population in this large-scale nationwide population study of Korean health insurance data.

References

[1]Garen T, Lerang K, Hoffmann-Vold A-M, Andersson H, Midtvedt Ø, Brunborg C, et al. Mortality and causes of death across the systemic connective tissue diseases and the primary systemic vasculitides. Rheumatology. 2018;58(2):313-20.

[2]Jang SY, Park TK, Kim D-K. Survival and causes of death for Takayasu’s arteritis in Korea: A retrospective population-based study. International Journal of Rheumatic Diseases. 2021;24(1):69-73.

[3]Hill CL, Cole A, Rischmueller M, Dodd T, Coleman M, Tucker G, et al. Risk of cancer in patients with biopsy-proven giant cell arteritis. Rheumatology (Oxford). 2010;49(4):756-9.

[4]Bicakcigil M, Aksu K, Kamali S, Ozbalkan Z, Ates A, Karadag O, et al. Takayasu’s arteritis in Turkey - clinical and angiographic features of 248 patients. Clin Exp Rheumatol. 2009;27(1 Suppl 52):S59-64.

[5]Park JK, Choi IA, Lee EY, Song YW, Lee EB. Incidence of malignancy in Takayasu arteritis in Korea. Rheumatol Int. 2014;34(4):517-21.

Disclosure of Interests

None declared

Active DNA damage eviction by HLTF stimulates nucleotide excision repair

Nucleotide excision repair (NER) counteracts the onset of cancer and aging by removing helix-distorting DNA lesions via a "cut-and-patch"-type reaction. The regulatory mechanisms that drive NER through its successive damage recognition, verification, incision, and gap restoration reaction steps remain elusive. Here, we show that the RAD5-related translocase HLTF facilitates repair through active eviction of incised damaged DNA together with associated repair proteins. Our data show a dual-incision-dependent recruitment of HLTF to the NER incision complex, which is mediated by HLTF's HIRAN domain that binds 3'-OH single-stranded DNA ends. HLTF's translocase motor subsequently promotes the dissociation of the stably damage-bound incision complex together with the incised oligonucleotide, allowing for an efficient PCNA loading and initiation of repair synthesis. Our findings uncover HLTF as an important NER factor that actively evicts DNA damage, thereby providing additional quality control by coordinating the transition between the excision and DNA synthesis steps to safeguard genome integrity.

Remifentanil requirement for acceptable intubation conditions with two different doses of ketamine without a neuromuscular blocking agent in pediatric patients

OBJECTIVE

The optimal remifentanil concentration for improving intubation conditions when intubation is performed without neuromuscular blocking agents (NMBAs) but with ketamine as an induction agent remains unknown. Here, we aimed to identify the effective bolus doses of remifentanil required to achieve acceptable intubation conditions upon anesthesia induction with 1 or 2 mg/kg ketamine without NMBAs.

PATIENTS AND METHODS

In this prospective, double-blinded, randomized up-down sequential allocation study, we enrolled pediatric patients aged 3-12 years undergoing general anesthesia for inguinal hernia surgery. The patients were randomly allocated to one of two groups to receive either ketamine 1.0 mg/kg (K1 group) or 2.0 mg/kg (K2 group) intravenously until seven success-failure pairs were achieved. The remifentanil dose for each patient was determined using the modified Dixon's up-and-down method with an initial dose of 2.5 μg/kg and a step size of 0.5 μg/kg.

RESULTS

In total, 51 patients (22 in the K1 group and 29 in the K2 group) were enrolled. The effective dose (ED)50s of remifentanil for obtaining clinically acceptable intubation conditions under anesthesia induction with ketamine but without NMBAs was 3.2 μg/kg in the K1 group and 1.6 μg/kg in the K2 group. High-dose remifentanil with 1 mg/kg ketamine was associated with more severe chest wall rigidity and lower mean blood pressure and heart rate than was low-dose remifentanil with 2 mg/kg ketamine.

CONCLUSIONS

The ED50 of remifentanil required for clinically acceptable intubation conditions with anesthesia induction using 1 mg/kg ketamine without NMBAs in pediatric patients was twice that when using 2 mg/kg ketamine. The combination of 2 mg/kg ketamine and remifentanil was better at preventing chest wall rigidity.

Ultrasensitive Detection of Fe3+ Ions Using Functionalized Graphene Quantum Dots Fabricated by a One-Step Pulsed Laser Ablation Process

With respect to the detection of Fe3+ ions, graphene quantum dots (GQDs) have limitations for commercialization owing to their high limit of detection (LOD). Here, we report a one-step pulsed laser ablation (PLA) process to fabricate amino-functionalized GQDs (FGQDs) for the efficient detection of Fe3+ using polypyrrole (PPy) both as a precursor (amine N) and as a surfactant and also using graphite as a carbon precursor. Using this method, the amine N groups were easily incorporated into the carbon network of the GQDs. Additionally, compared to pristine GQDs, FGQDs showed smaller particle sizes and narrower size distributions owing to the surface passivation effects of the PPy surfactant. Due to the synergistic effect of surface passivation and incorporation of amine N groups, FGQDs exhibited a sensitive response to Fe3+ ions in the concentration range of 500 nM to 50 μM, which is lower than the quality standards for Fe3+ ions (∼5.36 μM) as suggested by the World Health Organization (WHO). Furthermore, the processing time for synthesizing FGQDs by the PLA process was less than 30 min, thus allowing successful practical applications of GQDs in the sensing field.